From patchwork Wed Dec 20 14:57:26 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Fabrice Gasnier X-Patchwork-Id: 13500192 Received: from mx07-00178001.pphosted.com (mx07-00178001.pphosted.com [185.132.182.106]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3E7C1405D6; Wed, 20 Dec 2023 15:00:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=foss.st.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=foss.st.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=foss.st.com header.i=@foss.st.com header.b="ePcAbV5x" Received: from pps.filterd (m0288072.ppops.net [127.0.0.1]) by mx07-00178001.pphosted.com (8.17.1.22/8.17.1.22) with ESMTP id 3BKA44JO026222; Wed, 20 Dec 2023 16:00:23 +0100 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=foss.st.com; h= from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding:content-type; s= selector1; bh=VX1e1MqWUsqC3HC2njjApU0jyW7yAkL6duCodzEeM5Q=; b=eP cAbV5xk+x3Qo7PibNPS/EaLbPsy+ycxKxli2tbC2A2N05VXoSMvsH577BvcGHBVw WmKTJpAAvFE7m8wPJXpNNlR0RWJDwbdjwXXOFXpAsQEtUMB7XM7VXF67ylO5USG6 jR2Nr77V6kBeSxri7RlTLM7I/aR06+CQ2es6myuIDap8kXmneZVSLTNKcTf32mh6 jm3P6fBRzzSkGEKWH9wao+gUnnosz2SJ28qYNok3mUDcezVW8pVJ+48cMgisXYiw 8TbA9UStW4rqxxVahkvAH+eHmjBKJ5FZuY3p5c2Oi/Iixk13lFvZTtH1CULAZC9u fW87KI2+LKPlL9FMrTyQ== Received: from beta.dmz-eu.st.com (beta.dmz-eu.st.com [164.129.1.35]) by mx07-00178001.pphosted.com (PPS) with ESMTPS id 3v126m2j86-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 20 Dec 2023 16:00:23 +0100 (CET) Received: from euls16034.sgp.st.com (euls16034.sgp.st.com [10.75.44.20]) by beta.dmz-eu.st.com (STMicroelectronics) with ESMTP id C5C85100057; Wed, 20 Dec 2023 16:00:22 +0100 (CET) Received: from Webmail-eu.st.com (shfdag1node2.st.com [10.75.129.70]) by euls16034.sgp.st.com (STMicroelectronics) with ESMTP id B804321ADA0; Wed, 20 Dec 2023 16:00:22 +0100 (CET) Received: from localhost (10.201.20.59) by SHFDAG1NODE2.st.com (10.75.129.70) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.27; Wed, 20 Dec 2023 16:00:21 +0100 From: Fabrice Gasnier To: CC: , , , , , , Subject: [PATCH v3 10/10] counter: stm32-timer-cnt: add support for capture events Date: Wed, 20 Dec 2023 15:57:26 +0100 Message-ID: <20231220145726.640627-11-fabrice.gasnier@foss.st.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20231220145726.640627-1-fabrice.gasnier@foss.st.com> References: <20231220145726.640627-1-fabrice.gasnier@foss.st.com> Precedence: bulk X-Mailing-List: linux-iio@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-ClientProxiedBy: EQNCAS1NODE3.st.com (10.75.129.80) To SHFDAG1NODE2.st.com (10.75.129.70) X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.272,Aquarius:18.0.997,Hydra:6.0.619,FMLib:17.11.176.26 definitions=2023-12-20_09,2023-12-20_01,2023-05-22_02 Add support for capture events. Captured counter value for each channel can be retrieved through CCRx register. STM32 timers can have up to 4 capture channels (on input channel 1 to channel 4), hence need to check the number of channels before reading the capture data. The capture configuration is hard-coded to capture signals on both edges (non-inverted). Interrupts are used to report events independently for each channel. Signed-off-by: Fabrice Gasnier --- Changes in v3: - patch split from: "counter: stm32-timer-cnt: add support for events", to focus on the capture events only here. - only get relevant interrupt line --- drivers/counter/stm32-timer-cnt.c | 134 +++++++++++++++++++++++++++++- 1 file changed, 131 insertions(+), 3 deletions(-) diff --git a/drivers/counter/stm32-timer-cnt.c b/drivers/counter/stm32-timer-cnt.c index d13e4c427965..0b131ca71de6 100644 --- a/drivers/counter/stm32-timer-cnt.c +++ b/drivers/counter/stm32-timer-cnt.c @@ -263,6 +263,40 @@ static int stm32_count_prescaler_write(struct counter_device *counter, return regmap_write(priv->regmap, TIM_PSC, psc); } +static int stm32_count_cap_read(struct counter_device *counter, + struct counter_count *count, + size_t ch, u64 *cap) +{ + struct stm32_timer_cnt *const priv = counter_priv(counter); + u32 ccrx; + + if (ch >= priv->nchannels) + return -EOPNOTSUPP; + + switch (ch) { + case 0: + regmap_read(priv->regmap, TIM_CCR1, &ccrx); + break; + case 1: + regmap_read(priv->regmap, TIM_CCR2, &ccrx); + break; + case 2: + regmap_read(priv->regmap, TIM_CCR3, &ccrx); + break; + case 3: + regmap_read(priv->regmap, TIM_CCR4, &ccrx); + break; + default: + return -EINVAL; + } + + dev_dbg(counter->parent, "CCR%zu: 0x%08x\n", ch + 1, ccrx); + + *cap = ccrx; + + return 0; +} + static int stm32_count_nb_ovf_read(struct counter_device *counter, struct counter_count *count, u64 *val) { @@ -286,6 +320,8 @@ static int stm32_count_nb_ovf_write(struct counter_device *counter, return 0; } +static DEFINE_COUNTER_ARRAY_CAPTURE(stm32_count_cap_array, 4); + static struct counter_comp stm32_count_ext[] = { COUNTER_COMP_DIRECTION(stm32_count_direction_read), COUNTER_COMP_ENABLE(stm32_count_enable_read, stm32_count_enable_write), @@ -293,6 +329,7 @@ static struct counter_comp stm32_count_ext[] = { stm32_count_ceiling_write), COUNTER_COMP_COUNT_U64("prescaler", stm32_count_prescaler_read, stm32_count_prescaler_write), + COUNTER_COMP_ARRAY_CAPTURE(stm32_count_cap_read, NULL, stm32_count_cap_array), COUNTER_COMP_COUNT_U64("num_overflows", stm32_count_nb_ovf_read, stm32_count_nb_ovf_write), }; @@ -351,11 +388,68 @@ static int stm32_action_read(struct counter_device *counter, } } +struct stm32_count_cc_regs { + u32 ccmr_reg; + u32 ccmr_mask; + u32 ccmr_bits; + u32 ccer_bits; +}; + +static const struct stm32_count_cc_regs stm32_cc[] = { + { TIM_CCMR1, TIM_CCMR_CC1S, TIM_CCMR_CC1S_TI1, + TIM_CCER_CC1E | TIM_CCER_CC1P | TIM_CCER_CC1NP }, + { TIM_CCMR1, TIM_CCMR_CC2S, TIM_CCMR_CC2S_TI2, + TIM_CCER_CC2E | TIM_CCER_CC2P | TIM_CCER_CC2NP }, + { TIM_CCMR2, TIM_CCMR_CC3S, TIM_CCMR_CC3S_TI3, + TIM_CCER_CC3E | TIM_CCER_CC3P | TIM_CCER_CC3NP }, + { TIM_CCMR2, TIM_CCMR_CC4S, TIM_CCMR_CC4S_TI4, + TIM_CCER_CC4E | TIM_CCER_CC4P | TIM_CCER_CC4NP }, +}; + +static int stm32_count_capture_configure(struct counter_device *counter, unsigned int ch, + bool enable) +{ + struct stm32_timer_cnt *const priv = counter_priv(counter); + u32 ccmr, ccer, sr; + + if (ch >= ARRAY_SIZE(stm32_cc) || ch >= priv->nchannels) { + dev_err(counter->parent, "invalid ch: %d\n", ch); + return -EINVAL; + } + + /* + * configure channel in input capture mode, map channel 1 on TI1, channel2 on TI2... + * Select both edges / non-inverted to trigger a capture. + */ + if (enable) { + /* first clear possibly latched capture flag upon enabling */ + regmap_read(priv->regmap, TIM_CCER, &ccer); + if (!(ccer & stm32_cc[ch].ccer_bits)) { + sr = ~TIM_SR_CC_IF(ch); + regmap_write(priv->regmap, TIM_SR, sr); + } + regmap_update_bits(priv->regmap, stm32_cc[ch].ccmr_reg, stm32_cc[ch].ccmr_mask, + stm32_cc[ch].ccmr_bits); + regmap_set_bits(priv->regmap, TIM_CCER, stm32_cc[ch].ccer_bits); + } else { + regmap_clear_bits(priv->regmap, TIM_CCER, stm32_cc[ch].ccer_bits); + regmap_clear_bits(priv->regmap, stm32_cc[ch].ccmr_reg, stm32_cc[ch].ccmr_mask); + } + + regmap_read(priv->regmap, stm32_cc[ch].ccmr_reg, &ccmr); + regmap_read(priv->regmap, TIM_CCER, &ccer); + dev_dbg(counter->parent, "%s(%s) ch%d 0x%08x 0x%08x\n", __func__, enable ? "ena" : "dis", + ch, ccmr, ccer); + + return 0; +} + static int stm32_count_events_configure(struct counter_device *counter) { struct stm32_timer_cnt *const priv = counter_priv(counter); struct counter_event_node *event_node; u32 val, dier = 0; + int i, ret; list_for_each_entry(event_node, &counter->events_list, l) { switch (event_node->event) { @@ -366,6 +460,12 @@ static int stm32_count_events_configure(struct counter_device *counter) regmap_write(priv->regmap, TIM_SR, (u32)~TIM_SR_UIF); dier |= TIM_DIER_UIE; break; + case COUNTER_EVENT_CAPTURE: + ret = stm32_count_capture_configure(counter, event_node->channel, true); + if (ret) + return ret; + dier |= TIM_DIER_CC_IE(event_node->channel); + break; default: /* should never reach this path */ return -EINVAL; @@ -374,6 +474,15 @@ static int stm32_count_events_configure(struct counter_device *counter) regmap_write(priv->regmap, TIM_DIER, dier); + /* check for disabled capture events */ + for (i = 0 ; i < priv->nchannels; i++) { + if (!(dier & TIM_DIER_CC_IE(i))) { + ret = stm32_count_capture_configure(counter, i, false); + if (ret) + return ret; + } + } + return 0; } @@ -387,6 +496,12 @@ static int stm32_count_watch_validate(struct counter_device *counter, return -EOPNOTSUPP; switch (watch->event) { + case COUNTER_EVENT_CAPTURE: + if (watch->channel >= priv->nchannels) { + dev_err(counter->parent, "Invalid channel %d\n", watch->channel); + return -EINVAL; + } + return 0; case COUNTER_EVENT_OVERFLOW_UNDERFLOW: return 0; default: @@ -497,6 +612,7 @@ static irqreturn_t stm32_timer_cnt_isr(int irq, void *ptr) struct stm32_timer_cnt *const priv = counter_priv(counter); u32 clr = GENMASK(31, 0); /* SR flags can be cleared by writing 0 (wr 1 has no effect) */ u32 sr, dier; + int i; regmap_read(priv->regmap, TIM_SR, &sr); regmap_read(priv->regmap, TIM_DIER, &dier); @@ -504,7 +620,7 @@ static irqreturn_t stm32_timer_cnt_isr(int irq, void *ptr) * Some status bits in SR don't match with the enable bits in DIER. Only take care of * the possibly enabled bits in DIER (that matches in between SR and DIER). */ - dier &= TIM_DIER_UIE; + dier &= (TIM_DIER_UIE | TIM_DIER_CC1IE | TIM_DIER_CC2IE | TIM_DIER_CC3IE | TIM_DIER_CC4IE); sr &= dier; if (sr & TIM_SR_UIF) { @@ -515,6 +631,15 @@ static irqreturn_t stm32_timer_cnt_isr(int irq, void *ptr) clr &= ~TIM_SR_UIF; } + /* Check capture events */ + for (i = 0 ; i < priv->nchannels; i++) { + if (sr & TIM_SR_CC_IF(i)) { + counter_push_event(counter, COUNTER_EVENT_CAPTURE, i); + clr &= ~TIM_SR_CC_IF(i); + dev_dbg(counter->parent, "COUNTER_EVENT_CAPTURE, %d\n", i); + } + } + regmap_write(priv->regmap, TIM_SR, clr); return IRQ_HANDLED; @@ -627,8 +752,11 @@ static int stm32_timer_cnt_probe(struct platform_device *pdev) } } else { for (i = 0; i < priv->nr_irqs; i++) { - /* Only take care of update IRQ for overflow events */ - if (i != STM32_TIMERS_IRQ_UP) + /* + * Only take care of update IRQ for overflow events, and cc for + * capture events. + */ + if (i != STM32_TIMERS_IRQ_UP && i != STM32_TIMERS_IRQ_CC) continue; ret = devm_request_irq(&pdev->dev, priv->irq[i], stm32_timer_cnt_isr,